Welded Wire Lath

ABSTRACT

A welded wire mesh for use in securing stucco, plaster or other exterior finishing material to a building wall or other structure wherein the mesh comprises a matrix of longitudinally and transversely extending wires. The wires define intersections where the transversely extending wires are welded to the transversely extending wires and a plurality of deformations are formed in at least a portion of the wires between the intersections. The deformations cooperate with the stucco, plaster or other exterior finishing material to define a mechanical locking keys therebetween. The mesh can be disposed adjacent a flexible backing for providing a water vapor barrier, fire retardant or other desired property to the lath.

BACKGROUND OF THE INVENTION

The present invention relates to an improvement in welded metal wiremesh for enabling stucco, plaster or other exterior finishing materialsto bond to the surface of building walls or other structures. Weldedwire mesh provides a strong mechanical securement key for the stucco,plaster or other exterior material that would not otherwise be providedby the wall surface. The use of welded wire mesh or lath for suchpurposes is well known. Typically, such products are formed of a matrixof smooth, longitudinal and transverse wires defining a plurality ofsquares or rectangles. The wires are welded together at theintersections of the horizontal and transverse wires to provide astrong, durable mesh that can be used as a stand alone product securedto the surface to which the stucco, plaster or other material is to beapplied or, more commonly, with a moisture barrier backing sheet. In thelatter configuration, the wire mesh can be secured to the backing in avariety of ways, including the use of a mechanical locking system inwhich the backing is comprised of a sheet of uncoated haft paper and asheet of building paper or other material providing the moisture barrierthat is bonded to the kraft paper. During fabrication, the longitudinalor horizontal wires of the mesh are sandwiched between the two backingsheets. The vertical wires that traverse the horizontal wires aredisposed in front of the haft paper. Elongated perforations are providedin the haft paper to expose portions of the horizontal wires so that thevertical wires can be welded to the horizontal wires at their points ofintersection to mechanically couple the paper/rectangular wire lathcomposite. The present invention is directed to improving the mechanicalkeying of the stucco or other building material to the welded wire meshor lath and thereby enhancing the securement of stucco or other materialto the building wall without significantly impacting the cost of thelath or its ease of use.

SUMMARY OF THE INVENTION

Briefly, the present invention comprises an improved welded wire meshfor use in a wire mesh lath for enhancing the securement of stucco,plaster and other exterior finishing materials to a building wall orother surface. The enhanced securement is obtained by providingdeformations in the wire comprising the mesh, thereby creating amechanical interference fit between the wire mesh and the stucco,plaster or other material adjacent each deformation in the mesh as thematerial hardens about the wire mesh. The deformations in the wire, canbe formed by flattening longitudinally spaced portions along theotherwise smooth cylindrical wire, preferably, but not necessarily, onopposed sides of each wire. The deformations can be preformed in thewire or imparted to the wire during the construction of the lath,preferably prior to the welding together of the intersecting wires. Themesh can be disposed adjacent to a flexible backing for providing awater vapor barrier, fire retardant and/or other desired property to thelath.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a frontal plan view of a welded wire mesh lath comprising thepresent invention.

FIG. 2 is a frontal plan view of paper-backed welded wire mesh lathembodying the present invention.

FIG. 3A is an enlarged perspective view of a portion of a wire employedin the mesh of the present invention illustrating an example ofdeformations therein in accordance with the present invention formedtherein.

FIG. 3B is an enlarged side view of a portion of a wire employed in themesh of the present invention illustrating an example of deformationstherein in accordance with the present invention formed therein.

FIG. 4 is a cross-sectional view taken along the line 4-4 in FIG. 3A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now in detail to the drawings, an example of welded wire meshlath employing the present invention is illustrated in FIG. 1. The lath10 illustrated therein comprises a plurality of vertically spacedhorizontally extending wires 12 and a plurality of laterally spacedvertically extending wires 14 traversing wires 12 at intersections 16.Defoe nations 18 in the form of flattened surfaces are provided in aspaced disposition along wires 12 and 14. Wires 12 and 14 are weldedtogether at intersections 16 to define the welded wire reinforcing meshor lath 10. So configured, the lath 10 can be readily secured to abuilding wall or other structure, slightly proud of the outer surfacethereof, to provide an enhanced mechanical keying of the wire, adjacentthe deformations 18 therein, with the stucco, plaster or other exteriorsurface material as the material hardens about the wire mesh. The meshis typically positioned such that it is about half way through thethickness of the stucco or other material. This is accomplished by theuse of furring nails or in some cases a portion of the wire is bent toform a “stand off.” The enhanced keying effect results from theirregularities in the wire surfaces at the transitions 20 between thesmooth outer surfaces and deformed areas in the wire that abut thehardened stucco or other material. As a result of this enhanced keying,a more secure coverage of the building wall or other structure isobtained.

In the embodiment of the invention illustrated in FIGS. 1 and 2,self-furred, zinc coated 0.51 in. nominal diameter wire, cylindrical incross-section, is employed for both wires 12 and 14 at 1.5 inch verticaland horizontal spacings. The wires 12 and 14, however, can be formed ofany desired ferrous or non-metallic material including, bright,galvanized, plated or coated iron, carbon or alloyed steel or fromaluminum, stainless steel or brass and the spacing between the wires canbe varied. Also, both the horizontal and vertical wires 12 and 14 areprovided with spaced deformations 18 on opposed sides thereof to defineinterference fits between the mesh 10 and the stucco or other buildingmaterial (not shown). It is to be understood, however, that, if desired,the deformations could be formed in only the horizontal wires 12 or onlyin vertical wires 14 and/or at different locations along the wire. Also,while longitudinally spaced deformations in the form of flattened areasare preferably provided along the wires, other deformity configurationscould be provided in the wires to provide the desired interference fitswith the stucco, plaster or other building material. Further, thedeformations could be pre-formed in the wire or formed therein during orafter the formation of the wires 12 and 14 into the desired matrixpattern, but preferably, prior to the welding together of the verticaland horizontal wires.

A second embodiment of welded metal wire mesh or lath 100 is illustratedin FIG. 2. This embodiment differs from the prior embodiment in that itemploys a conventional backing 115 disposed about the plurality ofwelded horizontal wires 120 and vertical wires 140. In this embodiment,the mesh 100 can be identical to mesh 10 of the prior embodiment. Thebacking 115 can be of a composite configuration comprised of, forexample, a rearwardly disposed water vapor permeable sheet 160 made of,for example, asphalt paper, known as black paper, and a front sheet 165of separator paper, such as kraft paper, having a plurality of rows ofelongated perforations 170 formed therein. The wire mesh 100 can besandwiched between the rear and forward sheets 165 and 170 which can besecured together by a suitable adhesive (not shown) such that theintersections 116 of the horizontal and vertical wires 120 and 140 aredisposed within perforations 170 to provide access to the intersectionsfor the welding together of the wires, thereby securing together thewire mesh 100 and the composite backing 115 to form the lath 100. Inthis second embodiment, the horizontal wires 120 and vertical wires 140can be formed of the same materials as wires 12 and 14 of the priorembodiment and can be spaced apart distances ranging from about one totwo inches. In the embodiment of FIGS. 3 and 4, the deformations 180 arepreferably preformed in the wires to facilitate construction but couldbe formed during construction, as with the stand alone mesh 10 of theprior embodiment. The deformations 180 in the wires 120 and 140 alsocould vary in size, shape and location as in the prior embodiment.Different backings 115 could be employed to add additional or differentproperties to the lath, such as a sheet of a fire retardant material.

Various changes and modifications can be made in carrying out thepresent invention without departing from the spirit and scope thereof.Insofar as these changes and modifications are within the purview of theappended claims, they are to be considered as part of the presentinvention.

1. A welded wire mesh for use in securing an exterior finishing materialto a building wall or other structure as the material dries about andbonds to the wire mesh, said mesh comprising a matrix of longitudinallyand transversely extending wires, said wires defining intersections,said longitudinally extending wires being welded to said transverselyextending wires at said intersections, and a plurality of spaced surfacedeformations formed in at least a portion of said longitudinally and/ortransversely extending wires between said intersections, said surfacedeformations defining variations in the cross-sectional configuration ofsaid wires between said intersections and cooperating with the exteriorfinishing material to define a plurality of mechanical locking keystherebetween.
 2. The wire mesh of claim 1 wherein said longitudinallyand transversely extending wires are cylindrical in cross-section andsaid deformations define intermittent flattened surfaces in said wirebetween cylindrical portions of said wire and wherein the juncture ofsaid flattened and cylindrical portions of said wire comprise saidmechanical locking keys with the finishing material.
 3. A welded wirelath structure for use in securing an exterior finishing materials to abuilding wall or other structure as the material dries about and bondsto the wire mesh, said lath structure comprising a backing and a matrixof longitudinally and transversely extending wires secured to saidbacking, said wires comprising a matrix of longitudinally andtransversely extending wires, said wires defining intersections, saidlongitudinally extending wires being welded to said transverselyextending wires at said intersections, and a plurality of spaced surfacedeformations formed in at least a portion of said longitudinally and/ortransversely extending wires between said intersections, said surfacedeformations defining variations in the cross-sectional configuration ofsaid wires between said intersections and cooperating with the exteriorfinishing material to define a plurality of mechanical locking keystherebetween.
 4. The lath of claim 3 wherein said longitudinally andtransversely extending wires are cylindrical in cross-section and saiddeformations define intermittent flattened surfaces in said wire betweencylindrical portions of said wire and wherein the juncture of saidflattened and cylindrical portions of said wire comprise said mechanicallocking keys with the finishing material.
 5. The lath of claim 4 whereinsaid sheet of backing material defines a water vapor barrier for saidlath.